Start Time - The UTC date to start generating ephemerides. Must be in YYYY MM DD or JD format and must be between 2008 01 01 and 2015 12 31.

Stop Time - The UTC date to stop generating ephemerides. Must be in YYYY MM DD or JD format and must be between 2008 01 01 and 2015 12 31.

Horizon - The Sun's altitude (in degrees) when it is acceptable to observe. The default (-12) is somewhat earlier than astronomical twilight (-18), but is reasonable if observing bright targets. For reference, twilight flats are typically taken between -4 and -9 degrees. Must be between 0 and -90.

Airmass Limit - The maximum airmass of the object. Must be between 1 and 10. The default is 3.

Primary - If checked, it will display the visible primary transits (defined by horizon and airmass limit) during the specified window for the known transiting planets. These will be marked by Type = "P".

Secondary - If checked, it will display the visible secondary eclipses (defined by horizon and airmass limit) during the specified window for the known transiting planets. The calculated error assumes no uncertainty in the eccentricity or argument of periastron, so planets with eccentric orbits may have much larger uncertainties. These will be marked by Type = "S".

RV - If checked, it will display the time a primary transit would be visible (defined by horizon and airmass limit) during the specified window assuming the inclination were favorable. The calculated error assumes no uncertainty in the eccentricity or argument of periastron, so planets with eccentric orbits may have much larger uncertainties. These will be marked by Type = "R". The calculated durations make Hot-Jupiter-like assumptions if information is not available in the exoplanets.org database.

Earth-Based Observatory - A drop down menu of observatories. This will automatically retrieve the Latitude, Longitude, and Elevation of the observatory as defined in observatory.pro from the IDL astronomy library, last updated in July 2008 (using a list of observatories from noao$lib/obsdb.dat file in IRAF 2.11).

NOTE: observatory.pro contains the **West** longitudes, which we convert to East longitude before we use it. Do not enter the longitude from observatory.pro directly in the longitude box in this applet.

Latitude - The latitude of observatory, in decimal degrees. Must be between -90 and 90 degrees. Latitude and Longitude must be specified or both will be ignored.

Longitude - The East longitude of observatory, in decimal degrees (E Longitude = 360 - W Longitude). Must be between -360 and 360 degrees. Latitude and Longitude must be specified or both will be ignored.

JD_UTC Stop - The JD_UTC when you should stop observing -- this does not take into account the uncertainties in the ephemeris.

JD 1st Contact - The JD_UTC of 1st contact. The results are sorted by this column.

JD 4th Contact - The JD_UTC of 4th contact

Err(min) - The error in the central transit time (i.e., does not include duration error), in minutes

Reason - The reason the start/stop times were chosen -- either SUN, OBJ, or N/A.

• SUN - Start/stop observing as the sun sets/rises. You can change this slightly by adjusting the horizon limits.
• OBJ - Start/stop observing when the object rises/sets. You can change this slightly by adjusting the airmass limits.
• N/A - No reason; the time picked is 1 full duration before the central transit time (in order to have adequate baseline).

Frac2 - The fraction of the transit + baseline that is visible [ie, visible/(2*duration)].

Type - The type of observation (P = Primary transit, S = secondary eclipse, R = RV candidate)